Phytec phyCORE-i.MX 6, Hardware Manual

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Serial Interfaces
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PHYTEC Messtechnik GmbH 2016 L-808e_2
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In order to connect the module to an existing 10/100/1000Base-T network some external
circuitry is required. The required termination resistors on the analog signals (ETH0_A±,
ETH0_B±, ETH0_C±, ETH0_D±) are integrated in the chip, so there is no need to connect
external termination resistors to these signals. Connection to an external Ethernet
magnetics should be done using very short signal traces. The A+/A-, B+/B-, C+/C- and
D+/D- signals should be routed as 100 Ohm differential pairs. The same applies for the
signal lines after the transformer circuit. The carrier board layout should avoid any other
signal lines crossing the Ethernet signals.
Caution!
Please see the datasheet of the Ethernet PHY when designing the Ethernet transformer
circuitry or request the schematic of the applicable carrier board (phyBOARD-Mira i.MX 6)
as reference.
9.4.2 Software Reset of the Ethernet Controller
The Ethernet PHY at U2 can be reset by software. The reset input of the Ethernet PHY is
permanently connected to pad SD2_DAT1 (GPIO1_14) of the i.MX 6.
9.4.3 MAC Address
In a computer network such as a local area network (LAN), the MAC (Media Access Control)
address is a unique computer hardware number. For a connection to the Internet, a table is
used to convert the assigned IP number to the hardware’s MAC address.
In order to guarantee that the MAC address is unique, all addresses are managed in a
central location. PHYTEC has acquired a pool of MAC addresses. The MAC address of the
phyCORE-i.MX 6 is located on the bar code sticker attached to the module. This number is a
12-digit HEX value.